qapi: Use QAPI_LIST_PREPEND() where possible

Anywhere we create a list of just one item or by prepending items
(typically because order doesn't matter), we can use
QAPI_LIST_PREPEND().  But places where we must keep the list in order
by appending remain open-coded until later patches.

Note that as a side effect, this also performs a cleanup of two minor
issues in qga/commands-posix.c: the old code was performing
 new = g_malloc0(sizeof(*ret));
which 1) is confusing because you have to verify whether 'new' and
'ret' are variables with the same type, and 2) would conflict with C++
compilation (not an actual problem for this file, but makes
copy-and-paste harder).

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20201113011340.463563-5-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
[Straightforward conflicts due to commit a8aa94b5f8 "qga: update
schema for guest-get-disks 'dependents' field" and commit a10b453a52
"target/mips: Move mips_cpu_add_definition() from helper.c to cpu.c"
resolved.  Commit message tweaked.]
Signed-off-by: Markus Armbruster <armbru@redhat.com>

2 files changed, 3 insertions, 14 deletions

diff --git a/hw/core/machine-qmp-cmds.c b/hw/core/machine-qmp-cmds.c
index 87f1414..affffe0 100644
--- a/hw/core/machine-qmp-cmds.c
+++ b/hw/core/machine-qmp-cmds.c
@@ -215,7 +215,6 @@ MachineInfoList *qmp_query_machines(Error **errp)
 
     for (el = machines; el; el = el->next) {
         MachineClass *mc = el->data;
-        MachineInfoList *entry;
         MachineInfo *info;
 
         info = g_malloc0(sizeof(*info));
@@ -243,10 +242,7 @@ MachineInfoList *qmp_query_machines(Error **errp)
             info->has_default_ram_id = true;
         }
 
-        entry = g_malloc0(sizeof(*entry));
-        entry->value = info;
-        entry->next = mach_list;
-        mach_list = entry;
+        QAPI_LIST_PREPEND(mach_list, info);
     }
 
     g_slist_free(machines);
diff --git a/hw/core/machine.c b/hw/core/machine.c
index 05dcaf0..de3b8f1 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -504,11 +504,7 @@ static void machine_set_nvdimm_persistence(Object *obj, const char *value,
 
 void machine_class_allow_dynamic_sysbus_dev(MachineClass *mc, const char *type)
 {
-    strList *item = g_new0(strList, 1);
-
-    item->value = g_strdup(type);
-    item->next = mc->allowed_dynamic_sysbus_devices;
-    mc->allowed_dynamic_sysbus_devices = item;
+    QAPI_LIST_PREPEND(mc->allowed_dynamic_sysbus_devices, g_strdup(type));
 }
 
 static void validate_sysbus_device(SysBusDevice *sbdev, void *opaque)
@@ -569,7 +565,6 @@ HotpluggableCPUList *machine_query_hotpluggable_cpus(MachineState *machine)
 
     for (i = 0; i < machine->possible_cpus->len; i++) {
         Object *cpu;
-        HotpluggableCPUList *list_item = g_new0(typeof(*list_item), 1);
         HotpluggableCPU *cpu_item = g_new0(typeof(*cpu_item), 1);
 
         cpu_item->type = g_strdup(machine->possible_cpus->cpus[i].type);
@@ -582,9 +577,7 @@ HotpluggableCPUList *machine_query_hotpluggable_cpus(MachineState *machine)
             cpu_item->has_qom_path = true;
             cpu_item->qom_path = object_get_canonical_path(cpu);
         }
-        list_item->value = cpu_item;
-        list_item->next = head;
-        head = list_item;
+        QAPI_LIST_PREPEND(head, cpu_item);
     }
     return head;
 }